Suture type and ultrasound-indicated cerclage efficacy

Abstract

Objective: To assess whether type of suture material affects cerclage efficacy for preterm birth (PTB) prevention. Methods: Secondary analysis of a multicenter trial of ultrasound-indicated cerclage for short cervical length (CL), in which women with prior spontaneous PTB at 16–33 6/7 weeks, a singleton gestation and CL < 25 mm between 16–22 6/7 weeks, were randomized to McDonald cerclage or no cerclage. Outcomes of women who underwent cerclage were analyzed by type of suture material, comparing polyester braided thread (Mersilene™ or Ethibond™) to Mersilene tape™. Primary outcome was PTB < 35 weeks. Results: 138 women underwent McDonald cerclage: 84 (61%) received polyester braided thread and 46 (33%) Mersilene tape™. Eight (6%) received monofilament suture and were excluded from analysis. Rates of PTB < 35 weeks were similar, 35% for polyester braided thread vs 24% for Mersilene tape™ (p = .24). Birth gestational age was also similar among the 2 groups (p = .18). Conclusion: Type of suture material may not affect ultrasound-indicated cerclage efficacy in high-risk women with short CL, but further study is needed. Polyester braided thread (Mersilene™ or Ethibond™) and polyester braided Mersilene tape™ seem to have similar efficacy.

Keywords::

• Cerclage suture
• preterm birth prevention
• short cervical length

Acknowledgements

We wish to acknowledge other members of the Vaginal Ultrasound Trial Consortium: Susan Ramin, MD, Mark Tomlinson, MD, Eric Knudtson, MD, Robert Egerman, MD, Richard Silver, MD, Helen How, MD, Mike Gordon, MD.

Disclosure of Interest: All authors were the principal investigators in this NIH-sponsored prospective trials, with this secondary analysis proposed before the beginning of the study by VB, and approved by Dr. Owen and all others. Each author contributed to approval of the protocol, data collection and analyses. VB wrote the manuscript, with major help from JS (also statistical help) and JO, and all authors edited and contributed to the final version of the manuscript. Each of the centers obtained Institutional Review Board approval, and each woman signed informed consent at entry into the randomized study. The Eunice Kennedy Shriver National Institute of Child Health and Development provided funding via grant U01 HD039939; from the same agency, Dr. Owen also received support via grant 5K24 HD43314-5.